1. Field of the Invention
The present invention relates to a roller cleaning apparatus of a liquid electrophotographic printer, and more particularly, to a roller cleaning apparatus of a liquid electrophotographic printer for removing a developer film formed on a roller rotating in contact with a photoreceptor medium.
2. Description of the Related Art
In general, a liquid electrophotographic printer develops an electrostatic latent image formed on a photoreceptor medium such as a photoreceptor web with developer of a predetermined color and transfers the developed image to a print paper so that a desired image is printed.
The liquid electrophotographic printer, as shown in FIG. 1, includes a developing unit 20 for developing an electrostatic latent image formed on a photoreceptor web 10 with developer which is a mixture of powdered toner having a predetermined color, liquid carrier and other additives in a predetermined ratio, a drying unit 30 having a drying roller 31 for drying the developed photoreceptor web 10 and a heating roller 32, a transfer unit 40 for transferring the image on a surface of the photoreceptor web 10 via a transfer roller 41 and a fixation roller 42 to a print paper S.
The drying roller 31 absorbs the liquid carrier of the developer developed on the surface of the photoreceptor web 10. However, as the drying roller 31 contacts the photoreceptor web 10, not only carrier but also a small amount of toner is actually absorbed. Thus, with increased use of the drying roller 31, a developer contamination film can form on the outer circumferential surface of the drying roller 31.
Also, the transfer unit 40 transfers a toner image on the photoreceptor web 10 to the transfer roller 41 utilizing the difference in surface energy and then prints the image by transferring the toner image on the transfer roller 41 to a print paper S pressed by the fixation roller 42. However, in doing so, part of the toner image on the transfer roller 41 may be fixed on the surface of the transfer roller 41, forming a contaminated film. Also, as the developer is sticky, a paper jam can occur due to the print paper S adhering to the surface of the transfer roller 41 as the print paper S moves through the transfer unit 40.
Therefore, there is a need for a cleaning apparatus for cleaning the outer circumferential surfaces of the drying roller 31 and the transfer roller 41 where a developer contamination film can be easily formed, as they closely contact the photoreceptor web 10 where a toner image is developed.